/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.lucene.search.highlight;

/** Low-level class used to record information about a section of a document with a score. */
public class TextFragment {
  CharSequence markedUpText;
  int fragNum;
  int textStartPos;
  int textEndPos;
  float score;

  public TextFragment(CharSequence markedUpText, int textStartPos, int fragNum) {
    this.markedUpText = markedUpText;
    this.textStartPos = textStartPos;
    this.fragNum = fragNum;
  }

  void setScore(float score) {
    this.score = score;
  }

  public float getScore() {
    return score;
  }

  /**
   * @param frag2 Fragment to be merged into this one
   */
  public void merge(TextFragment frag2) {
    textEndPos = frag2.textEndPos;
    score = Math.max(score, frag2.score);
  }

  /**
   * @return true if this fragment follows the one passed
   */
  public boolean follows(TextFragment fragment) {
    return textStartPos == fragment.textEndPos;
  }

  /**
   * @return the fragment sequence number
   */
  public int getFragNum() {
    return fragNum;
  }

  /* Returns the marked-up text for this text fragment
   */
  @Override
  public String toString() {
    return markedUpText.subSequence(textStartPos, textEndPos).toString();
  }
}
